Nanoarchitectonics of polyaniline-derived porous carbons for efficient adsorptive denitrogenation of liquid fuel

Highly porous polyaniline-derived carbons (pDCs) were used as adsorbents to adsorb/remove hazardous organonitrogens (ONs) from liquid fuel for the first time. The nitrogen-rich pDCs were obtained via the carbonization of polyaniline (pANI) under an inert atmosphere. Further, the pDCs were activated in the presence of KOH (as a chemical activating agent) at different pyrolysis temperatures (600 to 800 degrees C) to increase the porosity or surface area of the pDCs. One pDC prepared at 700 degrees C (named pDC-700) showed very efficient adsorptions of representative ONs (indole and quinoline) from liquid fuel. The pDC-700 had a maximum adsorption capacity of 458 mg/g of quinoline which is the highest among the reported values with carbon-based adsorbents. The maximum adsorption capacity of the same adsorbent for the adsorption of indole (385 mg/g) was also very competitive against other carbonaceous adsorbents. The high adsorption capacities of the pDC-700 could be interpreted by a synergistic effect of an efficient hydrogen bonding (between the heteroatoms of pDC-700 and the adsorbates) and high microporosity of the adsorbent (SA(BET) > 2000 m(2)/g). In addition, a simple solvent washing could regenerate the pDC-700 for the successive utilization in adsorptions effectively.

Automated summary

Highly porous polyaniline-derived carbons were used as adsorbents for the first time to remove hazardous organonitrogens from liquid fuel. The pDCs showed high adsorption capacities, especially the pDC-700 prepared at 700 degrees C. The high adsorption capacities can be explained by efficient hydrogen bonding and high microporosity of the adsorbent. Moreover, the pDC-700 can be regenerated for successive utilization through solvent washing.